Holdly SP20172 Flammable Vapor FV Sensor Kit AP13447-3-25VS for Rheem/Ruud/Richmond FVIR Water Heaters

Enhance safety with a trusted FV sensor kit

The Holdly SP20172 Flammable Vapor FV Sensor Kit is a practical replacement part designed for FVIR water heaters. It includes a Flammable Vapor Sensor (AP13447-3 - 25VS), a Cap Plug, and a Wire Tie. The kit is compatible with Rheem (Ruud, Richmond) FVIR models, and also fits certain AO Smith and Bradford White units.

The flammable vapor sensor film responds to gasoline vapors by changing its electrical resistance. That signal is read by the water heater's control circuit, helping the system decide whether to continue heating. No external power is required—the sensor relies on the control circuit's power to monitor resistance changes and process the data. This keeps the replacement simple and compact while preserving the original design intent.

When the sensor detects vapor, the control module can shut off the gas supply to the water heater to prevent ignition. This behavior aims to reduce safety risks while keeping downtime minimal and hot water available after a quick replacement.

After installing the sensor, many users report the water heater returning to normal operation more quickly, with hot water restored as expected. For compatibility questions, reach out and we’ll help confirm fit for your model.

What’s in the box

• Flammable Vapor Sensor AP13447-3 - 25VS
• Cap Plug
• Wire Tie

Key benefits you might notice

• Faster restoration of hot water after a sensor replacement
• Simple, tool-light installation that preserves control circuitry
• Broad compatibility with multiple FVIR water heater brands
• Reduced risk of ignition in areas with fuel vapors

Real-world scenarios

• Replacing an aging sensor in Rheem/Ruud Richmond FVIR heaters
• Upgrading to a newer AP13447-3 sensor in AO Smith or Bradford White FVIR units
• Maintaining safe operation in spaces where gasoline vapors might be present

Note: This is a replacement part for select FVIR water heaters. If you’re unsure about compatibility, contact us with your model number and we’ll check it for you.